Patent GB-640148-A (GB)
Title: Aliphatic sulphur compounds and compositions containing same
Filed: 1946-10-22
Abstract: Aliphatic sulphur compounds obtained by heating an aliphatic sulphide containing not less than 14 carbon atoms in the molecule with sulphur and/or selenium (see Group IV (b)) are used to stabilize, e.g. viscose oily polymers of propylene oxide.  They are preferably used in amounts of 0.2 to 1 per cent by weight, based on the finished oil composition or greater amounts, e.g. 2 to 25 per cent may be used to produce concentrates for later blending with more oil.ALSO:Aliphatic sulphur compounds useful as anti-oxidants especially for mineral lubricating oils are obtained by heating a mixture of an aliphatic sulphide containing at least 14 carbon atoms in the molecule with sulphur or selenium at a temperature and for a time sufficient to combine stably with the aliphatic sulphide 15 to 45 per cent by weight of sulphur or 10 to 45 per cent of selenium or 15 to 45 per cent of a mixture of sulphur and selenium based on the weight of sulphur originally present in the sulphide so that said added element exhibits substantially no tendency to separate on cooling to 77 DEG F.  The aliphatic sulphide used as starting material contains in the molecule one or more groups \sYC-(S)n-C\sZ, wherein the carbon atoms are aliphatic and n is 1, 2 or 3, preferably 1 or 2.  There may be a plurality of such groups in one molecule, thus poly-monosulphides and poly-disulphides may be used.  The radicals attached to the sulphur may be open chain or cyclic aliphatic radicals, saturated or unsaturated, and may be substituted by polar groups or by aromatic radicals.  Specified sulphides are cetyl ethyl monosulphide, didecyl-, dilauryl-, dicetyl- and dibenzylmonosulphides; didecyl-, dilauryl, dibenzyl- and dicetyl disulphides; didodecyl ethylene dithioether, dimonosulphides of the type R-S-(CH2)n-S-R wherein the R's are aliphatic groups and n is 1 or 2 and the products of condensing polychlorinated aliphatic hydrocarbons with sodium monosulphide. Also specified are didodecyl ethylene di-disulphide and di-disulphides of the type R-S2-(CH2)n-S2-R where the R's are aliphatic groups and n is 1 or 2, and the products of condensing polychlorinated aliphatic hydrocarbons with sodium disulphide. The preferred aliphatic sulphides are the diparaffin sulphides obtained by condensing chlorinated paraffin wax with an alkali p  metal monosulphide, an alkali metal polysulphide or a mixture of an alkali metal sulphide and sulphur.  The paraffin wax used is preferably one having a melting point of 120 DEG  to 160 DEG  F. and this is chlorinated to about 15 to 25 per cent chlorine content.  Any form of free sulphur or selenium may be used, e.g. flowers of sulphur, roll sulphur and red selenium.  Mixtures of selenium and sulphur may be used.  The reaction temperature is preferably 275 DEG  to 350 DEG  F. In examples: (1) chlorinated paraffin wax is prepared by chlorinating a 130 DEG  F. melting point paraffin wax to 20 per cent chlorine content by bubbling chlorine through it at 190 DEG  to 200 DEG  F. The chlorinated wax is then added slowly to a refluxing mixture of alcohol, sodium monosulphide and sulphur in a pressure vessel.  The mixture is finally heated to 270 DEG  F. under increased pressure. The pressure is then released, the alcohol distilled off and the mixture diluted with petroleum thinner to deposit sodium chloride. The thinner solution is filtered and the thinner distilled off.  The diparaffin sulphide obtained is then heated to 300 DEG  F. in a jacketed steel mixture and flowers of sulphur added slowly, the mixture being then maintained at 300 DEG  F. for a further period of time to yield a product from which no sulphur separates out on cooling; (2) a diparaffin sulphide prepared as in (1) is heated with selenium at 375 DEG  F., yielding a dark brown product. Further examples are given (see Group III) to illustrate the use of the products of examples (1) and (2) as antioxidants in mineral lubricating oils.  U.S.A. Specification 2,346,157 is referred to.ALSO:Aliphatic sulphur compounds obtained by heating an aliphatic sulphide containing not less than 14 carbon atoms in the molecule with sulphur and/or selenium (see Group IV (b)) are used to stabilize hydrocarbon and non-hydrocarbon lubricating oils, e.g. light to heavy petroleum lubricating oils of naphthenic, paraffinic and mixed base origins, vegetable oils and viscous oily polymers of propylene oxide. They may be used in amounts of 0.1 to 2 per cent by weight based on the finished composition or greater amounts, e.g. 2 to 25 per cent may be used to produce concentrates for later blending with more oil. They may be used in mineral lubricating oils in conjunction with oil-soluble polyvalent metal salts of organic acids or organo-substituted inorganic acids, oil-soluble polyvalent metal salts of phenols, i.e. phenates such as the calcium, barium and aluminium salts of cetyl phenol and diamyl diphenol monosulphide, oil-soluble polyvalent metal organo sulphonates such as calcium, barium and aluminium mahogany sulphonates and oil-soluble calcium, barium and aluminium alkyl benzene sulphonates; phosphates and thiophosphates such as calcium and zinc salts of dicetyl phosphoric acid, dimethylcyclohexyl dithiophosphoric acid and dicetyl phenyl dithiophosphoric acid and other oil-soluble polyvalent metal salts of organo substituted sulphur-containing acids of phosphorus; calcium, barium and aluminium naphthenates and calcium and barium salts of aliphatic carboxylic acids such as a -phenyl stearic acid, a -cetyl succinic acid and the acid lauryl ester of succinic acid.  In examples: (1) the product obtained by heating chlorinated paraffin wax with sodium monosulphide and sulphur to form a diparaffin sulphide and then heating the latter with sulphur or selenium, is added to heavy white oil and subjected to oxidator tests; (2) a blend of solvent refined California paraffinic and naphthenic oils containing a small amount each of calcium dicetyl phenyl dithiophosphate, a sulphurized phenate (product of heating sulphur with the calcium salt of an alkylated phenol produced by alkylating phenol with a butene polymer) and of the sulphur-diparaffin sulphide product of (1) is subjected to an engine performance test; (3) as in (2) but using solvent-refined California paraffinic oil as base oil; (4) as in (2) but using a highly-refined mixed base oil from mid-continent crude (mixed asphaltic paraffinic base). Comparative examples are given in each case using the intermediate diparaffin sulphide product of example (1) instead of the sulphur-sulphide or selenium-sulphide product.